swal alert string validation with error on same popup code example

Example 1: sweetalert2 if else

swal({
  title: 'Input something',
  input: 'text',
  showCancelButton: true,
  inputValidator: function(value) {
    return new Promise(function(resolve, reject) {
      if (value) {
        resolve();
      } else {
        reject('You need to write something!');
      }
    });
  }
}).then(function(result) {
  swal({
    type: 'success',
    html: 'You entered: ' + result
  });
})

Example 2: sweet alert

swal("Good job!", "You clicked the button!", "success");